Production of sulphonation derivatives



' Patented Many 26, 1940 UNITED STATES PATENT orrics PRODUCTION OF SULPHONATION DERIVATIVES "Wendell W. 'Moyer, Decatur,

Ill., assignor to The Solvay Process Company, New York, N. Y.,

a corporation of New York No Drawing.

Application September 12,1938, Serial No. 229,534

Claims. (erase-40o) Another object ofthe invention is to provide u a process for the production 'of products comprising essentially alpha-sulphonic acid derivatives of saturated higher fatty acids which may I be carried out efliciently on a commercial scale.

Other objectsi-of the invention will in part be.

obvious and will in part appear hereinafter.

It has been discovered in accordance with the present invention that by sulphonating amides of saturated higher fatty acids with sulphur trioxide in the presence of liquid sulphur dioxide valuable products are obtained which contain an important amount of alpha-sulphonic acid derivatives of saturated higher fatty acids rather than products which consist only of the sulphonation derivatives of the amides themselves, as might be expected. In carrying out the sulphonation of these amides, it has been found to be important if products of good quality are to be obtained that. the saturated higher fatty acid.

amide or mixture of amides used as the starting 5 material should not contain an excessive amount of amides of unsaturated higher fatty acids. For example, it has been found that the amides of saturated higher fatty acids used as the starting materials in the process should be free from more 9 than five per cent, and especially two per cent,

by weight of amidesof unsaturated higher fatty acids.

control the amount of water present in the sulphonation reaction mixture. Thus, it has been found that as the water present in the reaction mixture is increased, there is a corresponding decrease in the yields of the desired products. Further, while in the use of a reaction mixture 50 containing a material amount of water, the yields may be improved by increasing the vigor of the sulphonating conditions. such as the temperatures, this is not satisfactory because the products obtained are of inferior color, indicating a relatively large amount of impurities therein.

higher fatty acid radicals,

It has also been found to be important to The color of these products is inferior to the color of products obtainable in'the same yields by a process involvingthe use of a reaction mixture containing a smaller proportion of water. It has been found that'the sulphonation reaction should 6 be carried out under conditions such that there is present in the mixture not more than three per cent of water based on the weight of sulphur triovide used in the reaction. Further, the

best results are obtained if the reaction is car- 10 ried out under substantially anhydrous conditionsj i. e.,,under conditions such that there is present in the reaction mixture not more than one per cent of water based on the weight of sulphur trioxide used.

It is surprising .that this process is productive of, the results noted since the usual sulphonating procedures, if applied to the sulphonation of amides of saturated higher fatty acids, are unsatisfactory because they result in the production 20 of dark-colored products or in a small degree of sulphonation. Thus, if oleum, concentrated sulphuric acid, or chlorsulphonic acid is used in the sulphonation, significant yields ofsulphonation products are not obtained at low tempera- 25 tures, while at high temperatures serious car-v bonization of the organic material occurs. It appears that the results obtainedwitholeum and sulphuric acid are due to the fact that these agents contain combined water which is deleterious. 3o

Chlorsulphonic acid is undesirable for the further reason that hydrochloric acid is formed which must be removed.

The products of the present process, which are preferably employed in the salt form, in ,general consist of mixtures of alpha-sulphonic acidderivatives of the saturated higher fatty acids whose amides have been used as the starting materials in the process, alpha-sulphonic acid derivatives of the amides themselves, and other 40 nitrogen-containing alpha-sulphonic acid derivatives of saturated higher fatty acid compounds which are believed to'be sulphonamides. These products as such, or in admixture with salts such as, 'for example, sodium sulphate or'ammonium sulphate, are valuable detergent, wetting, emulsifying, and the like agents which are active in hard water and in. acid and alkaline solutions. Thus, as compared with ordinary soaps they are not hydrolyzed to the free unsulphonated fatty acids in acid solutions. Also, they do not have the disadvantage of soaps of being precipitated in the form of sticky curds from solutions containing calcium or magnesium salts which have no detergent value but which ll constitute impurities. As compared with ordinary sulphonated fatty acids obtained by the sul- 'rally occurrlng fats and oils phonation of unsaturated and/or hydroxy fatty acids, of which Turkey red oils are outstanding examples, the products possess considerably superior wetting and detergent properties and are more stable against hydrolysis. The properties of the products, as compared with the properties of ordinary sulphonated fatty acids, appear to be due to the facts that the sulphonic acid group in the derivatives in the products is at the end of a long carbon chain, and they contain a sulphon'ic acid group rather than the more easily hydrolyzed sulphuric acid ester group.

The starting material employed in the present 8 .to'24, and especially from 14 to 18, carbon.

atoms. Examples of such a fatty acids are the following: myristic acid, palmitic acid,- stearic acid, arachidic acid, behenic acid, and lignoceric acid.

The process is preferably carried out using amides of saturated higher fatty acids derived from naturally occurring fats or oils of which tallow, cocoanut oil, babassu oil, palm oil, and fish oils; e. g., menhaden fish oil, are examples, as

starting materials. The naturally occurring fats or oils may be used as the initial starting materials in the process. In this case it is advisable to subject them to hydrogenation as the first stepin the process. As is well known, the natuare composed of glycerides of unsaturated as higher fatty acids: tallow, for example, contains glycerides of the saturated fatty acids, stearic acid, palmitic acid, and myristic acid; and glycerides of the unsaturated fatty acids, v oleic acid, and linoleic acid. The hydrogenation of a fat or oil is preferably effected by contacting the material with hydrogen at an elevated temperaf ture and at a superatmospheric pressure in the presence of a hydrogenation catalyst, such as nickel. The product obtained as a result of this treatment is composed substantially entirely of glycerides of saturated fatty acids.

Amides adapted for use in,the present process can be obtained from a hydrogenated fat or oil by first hydrolyzing the fat or oil to the free acids and glycerine and then, after removing the glycerine, amidating the free acids with ammonia. The amides can also be prepared from the hydrogenated fat or oil directly by subject ing the fat or oil to ammonolysis in any con-' venient or desired manner, several of which are well known in the art. The amides formed in this way can be easily separated from the remainder of the reaction mixture by distillation under vacuum.

The amides prepared by ammonolysis of a hydrogenated fat'or oil or in any other suitable manner, are sulphonated in accordance with the present invention by-bringing them into reac-' tive contact with sulphur trioxide in the presence of liquid sulphur dioxide as the solvent medium. This is preferably carried out by dissolving and/or suspending the amides in liquid well as saturated 3195,1158 I v sulphur dioxide, and then introducing sulphur trioxide, which is conveniently in solution in liqor suspension. At the completion of 'the sulphonation, the sulphonation derivatives are'recovered from the remainder ofthe reaction mixture as such, or in admixture with sulphates.

For examp1e,'the liquidosulphur' dioxide may be distilled oil? and condensed for use ina succeeding run of the process.

When the process is operated by removing the bulk of the liquid sulphur dioxide by distillation, the mixture remaining is treated so as to convert the sulphonation derivatives, which are present in the free acid form, to the salt form.

This is conveniently accomplished by introducing the mixture into water, and then neutralizing the resulting aqueous mixture with a suitable alkaline material; .e. g., with sodium hydroxide. The neutralizing agent may be added in such proportions as to form predominantly partial salts of the sulphonation derivatives or in hand, the partially neutralized aqueous mixturemay be dried whereby there is. obtained a dry product consisting of the partial salts of the sulphonation derivatives in admixture with sulphates formed by reaction between the alkaline neutralizing agent and sulphuric acid forme'din the reaction, and between ammonia released in the reaction and the sulphuric acid. If the neutralization. has been carried out so as to form the wholly neutralized salts of the sulphonation derivative s, the neutralized mixture is preferably dried, as by means of a spray or rotary drum drier, whereby there is obtained a dry product similar to that described above except that it contains the wholly neutralized, rather than the partially neutralized, salts of the-derivatives.

As before indicated, the products of the present invention ordinarily are mixtures of the salts of alpha-sulphonic acid derivatives of saturated higher fatty acids, alpha-sulphonic acidderivatives of saturated higher fatty acid amides, and

4 uid sulphur dioxide, into the resulting solution alpha sulphonic acid derivatives of nitrogencontaining saturated higher fatty acid com pounds which are believed to be sulphonamides. This mixed product is a valuable product and for most purposes is at least as valuable as a product in which the essental detergent ingredientis the alpha-sulphonic acid derivative of a saturated higher fatty acid. For certain purposes, however, it may be found of advantage to convert it to a product. whichfis substantially free from sulphonated amides or other nitrogen containing sulphonation derivatives. As a feature of the invention it has been found that this may be accomplished in a simple manner by subject ing the product to a hydrolysis treatment with an acid such as, for example, hydrochloric acid. The hydrolyzed product on neutralization with a suitable alkaline material, such as sodium hydroxide, consists essentially of salts of alphasulphonic. acid derivatives of saturated higher fatty acids, sulphates, and salts of the acid employed in the hydrolysis reaction.

The salts present in the products appear to improve the valuable properties of the products.

If desired, salts (in addition to those formed in I phate, disodium phosphate,

- ami g understood that additional salts may beadded the reaction) such as, for example, sodium sulphate, ammonium sulphate, monosodium phosborax, sodium silicate, and sodium sesquicarbonate, can be added to the products, Also, be found of advantage nets with other detergents and/or wetting agents, such as ordinary soaps and other sulphonated products.

In order that understood, referenceshould be had to the following speclflc examples in which are disclosed processes coming within the scope of the present invention. It will be understood that these examples are given for illustrative purp ses merely and are not intended as limitations of the invention. The parts are by weight and the temperatures are in degrees centigrade. 7

Example 1.l parts of saturated higher fatty acid amides having an average carbon content of l! to 18 atoms per molecule and containing less than two per cent by weight of amides of unsaturated higher fatty acids, are dissolved and/or suspended in substantially anhydrous liquid sulphur dioxide in a suitable vessel capable of withstanding moderate pressures. A mixture containing one mol of sulphur trioxide and 50 to 70 mols of anhydrous liquid sulphur dioxide provided with a sealing means.

is added continuously with vigorous stirring over a period of about two hours; the rate of introduction of the solution of sulphur trioxide and sulphur dioxide being such that about three mols of sulphurtrioxide are introduced for each mol of the saturated higher fatty a d amides contained in the reaction mixture. The temperature of the reaction mixture is controlled during the addition so as to lie within the range of to and the reaction is permitted to continue for an additional two hours at said temperature. In order to avoid loss .of sulphur dioxide and to assure satisfactory progress of thereaction, the presure is maintained at about the vapor pressure of sulphur dioxide at the existing temperature, At the completion of the sulphonation, which will require about four hours under these conditions, substantially all of the sulphur dioxide is vaporized from the reaction mass, condensed in a receiver, and stored for, use in a succeeding run of the process. The mass remaining after the removal of the bulk of the sulphur dioxide is dissolved in a minimum quantity of water and the resulting aqueous mixture is heated to remove residual sulphur dioxide. The aqueous mixture obtained in this way is then neutralized to a pH of! with an aqueous caustic soda solution: The mixture after neutralization is in the form of a slurry containin the sodium salts of the sulphonation derivatives present therein. This slurry is dried as by means of a-spray or rotary drum drier to form a dry product which has valuable detergent, wetting, emulsifying, and the like properties.

Example 2.4.54 parts of myristamide are mixed with 9.6 parts of sulphur trioxide'in about 143 parts of liquid sulphur dioxide in a vessel The vessel is then sealed and is maintained at room temperature for about 24 hours. The vessel is then opened, the sulphur dioxide is distilled off, and the residue is introduced into water and treated for the'preparation of a detergent product. For example, the aqueous mixture can he neutralized and further treated as described in Example 1.

When proceeding in accordance with the general procedure of the above examples it will be in certain cases'it may to combine thedry prodthe invention may be more fully during the neutralization and drying procedures (e. g., up to 20 to 50 per cent by weight of the sulphonated compound), or, if desired, an excess.

of sulphur trioxide over .that required in the sulphonation may be used and neutralized with an alkaline material (e. g., a caustic alkali or ammonia) to form in situ asalt constituting a,

It will be understood, of course, that the starting materials employed in the examples may be replaced by amides of other saturated higher fatty acids; e. g., any of those referred to above. Fur-. ther, while it is preferred to employ as the starting'materials in the present process amides which are unsubstituted in the amino groups, it is possible to employ amides which contain as N-substituents low molecular aliphatic radicals free from reactive substituents. As examples of amines whose amides are of interest in this connection, the following may be mentioned by way of example: methyl amine, dimethyl amine, ethyl amine, diethyl amine, methyl ethyl amine, and

methoxyethyl methyl amine.

In place of the neutralizing agents used in the examples, there may be used any other alkaline material capable of reacting with a sulphonicthe process can be varied within relatively wide I limits but in order to produce satisfactory yields of the desired products, it should not be reduced below 2.5 molsfor each mol of the saturated amide or amides subjected to. treatment. On the other hand, it is ordinarily unnecessary toemploy more than 4 mols of sulphur trioxide per mol of amide. For'most efficient operation it is preferableto employ from 3 to 3.5 mols of sulphur trioxide for each mol of the saturated fatty acid amide. An excess of sulphur trioxide ordinarily does not have a critical effect on the operativeness of the process, and in some cases where it is desired to form a sulphate in situ. it is of advantage. With respect to the amount of liquid sulphur dioxide required as the solvent medium it will be understood thatthis amount is dependent in large measure upon the solubility in this medium of the particular saturatedfatty acid amide or mixture of amides used as the starting material in the process. A relatively large amount of liquid sulphur dioxide may be used in the reaction without materially adding to the cost of the process since the sulphur dioxide may be efllciently recovered for reuse in a succ eding run of the process by distillation and condensation. I

The sulphonation reaction can be carried out at ordinary temperatures and because of simpl city of operation such temperatures are usually employed. If desired, however, a higher or lower temperature can be used, for example, temperatures varying from 20 to C. are suitable. The time required for the sulphonation reaction the specific saturated fatty acid amide or amides subjected to treatment, the apparatus employed, the temperature, andother conditions. Under ordinary conditions of operation, a reaction period of from 3 to'20 hours 'is sufl'icient to comis also a variable factor, being dependent upon 5 of the invention, the above description should be saturated higher fatty 'acids' which comprises 5-- interpreted as illustrative and not in a limiting sulphonating an amide of a saturated higher .fatsense I ty acid-containing not substantiallymore. than I claim: flveper f cent pf amides of unsaturated higher l. The process for the preparation of alphafatty acids with sulphur trioxide under substansulphonic acid derivatives of saturated higher tially anhydrous conditions in a reaction mix- 10: fatty acids which comprises sulphonating an am turein whichliquid sulphur dioxide is the solvent ide oi asaturated higher fatty acid'withs'ulphurmedium: distilling 'oflsulphur dioxide-from the trioxide in the presence of liquid sulphur dioxide." reaction mixture, m ng the remainder of the 2, The process for tha-preparati'on of 'alpha-= reaction mixture'withswatermeutralizing the re- 5 sulphonic acid derivatives of saturated higher' suiting-aqueous mixture, and drying the neutralfatty acids which comprises sulphonating anized mixture. amide of a saturated higher 'fattyacid contain-- 8. The processj for the preparation of a detering 8 to 24' carbon atoms and containing-notgent product commflsing.-alpha-sulphonic acid substantially more than five per centfof amides. derivatives-cf-saturated 'higher' fatty acids and ..of unsaturated -higher fattyacids with-sulphuralph -sulphqnim acid-derivatives'of amides of 20 trioxide'in-the presence of liquid sulphurdioxide. saturated -h18herfatty acids which "comprises '3. 'The-processfor the preparation of alphaforming a substantially anhydrous reaction-mix sulphonic acid derivatives of' saturated higher ture comprising one moi-of an-amide of-a satfatty acids which comprises-'sulphonating an urated higher-"fatty acid containing notsub-- 25 :amide 'of-a-satllrated higher fattyacid contain stantially more than two per cent of amides ch25.- ing 8 to 24' carbonatoms and containing not subunsaturated higher-fatty acids-and-3-to-3.5 molsstantiallymore-than five percent of'amides of of :sulphur trioxide in-a, solvent medium comunsaturated-higher fatty acids with sulphur tri-- posed substantially 'ofliquidsulphurdioxide,-

- oxide ina-reaction mixture in which liquid sulmaintaining the reaction mixture at a--tempera-- 3o phur' dioxide-lathe solvent medium, said reac- 4 ture of 20ito 50 C. 'ior 3 to-20 hours, wherebyq a0 no ixtu being tre from more than three there are formed in the reaction mixture sul-" per cent of waterbased on the weight of sulphur phonation-derivatives comprising the alpha-suitrioxidea 4 h phonic acid-.derivativeof the saturated higher 4. The process for 'the preparation of alphafatty acid corresponding to said amide of a satu- .35 sulphonic acid derivatives-of saturated higher rated higher fatty acid and the alpha-sulphonic r86 single amides.

Since certain changes may be made'in the above process without departing from the scope i'attyacids,which-comprises sulphonating 'an to 4 mols ofsulphur trioxide for each moi of said amide-of a saturated higher fatty acid in the sulphonic acid derivatives of saturated higher presence-ofliquid'sulphur dioxide under substanfatty acids which comprises sulphonating an tially anhydrouscondition's. I i amide 'of a saturated higher fatty acid con- .5. The. processffor the preparation of the altaining 8 to 24 carbon atoms and containing not pha-sulphonic. acid derivative of myristic acid substantially morezthan five per cent of amides which.comprisessulphonating myristamide con-- of.unsaturated higher fatty acids with sulphur taining nottsubstantialiy more than live per cent trioxide in thepresence of liquid sulphur dioxide, oiamides .of unsaturated higher fatty acids with whereby'a mixed sulphonation product containsulphur trioxide in the presence of liquid sulphur lng nitrogen is produced, and hydrolyzing said 5o dioxide under substantially anhydrous conditions. mixed suiphonation product toremove nitrogen 6-; The process for the preparation of alphatherefrom. sulphonic .acid derivatives of saturated higher 10. The process for the preparation of alphafatty acids which. comprises sulphonating ansulphonic acid derivatives of saturated higher amide ota saturated higher fatty acid containing fatty acids which comprises sulphonating an not. substantially more than five percent of amide of a saturated higher fatty acid contain- 5 amide of a,saturated higher fatty acid containing not substantially more than five per cent of amidesof-unsaturated-higher-fatty acids with 2.5

amides of unsaturated higher fatty-acids with 2.5 to 4 mols of sulphur trioxide in the presence of liquid sulphur dioxide under substantially anhydrous conditions at a temperature of 20 to 50 C. for 3 to 20 hours.

acid derivative of said-amide,

9,195,188 7 to include mixtures of such ammo. as well as -7. The process for the-preparation of a detergent product comprising alpha-sulphonic'acid derivatives of saturated higher fatty acidsand alpha-sulphonic acid derivatives of amides of separating the sulphonation derivatives from the liquid sulphur dioxide, and neutralizing the suiphonation derivatives.

-9. The process for the preparation of alphaing not substantially more than five per cent of amides of unsaturated higher fatty acids with sulphur trioxide in a reaction mixture in which liquid sulphur dioxide is the solvent medium.

. WENDELL W. MOYER. 

